GB1354258A - Submergible tank - Google Patents

Abstract

1354258 Submarine storage tanks SEA TANK CO 1 March 1972 [5 March 1971] 9640/72 Heading E1H A submarine hydrocarbon storage tank I made of prestressed reinforced concrete and having a planar bottom 10 and an upswept cover 2 between which reinforcing pillars 21 extend, is divided by walls 5, 6 into a plurality of cells, the peripheral cells 3 which are open to the water and which intercommunicate through single apertures 7c acting as ballasting cells, and the inner cells 4 which intercommunicate through upper and lower apertures 7a, 7b acting as storage cells. Some of the apertures 7a, 7b, 7c may be selectively closable. The ballasting cells 3 form two symmetrically located cell groups, one group being composed of the cells in corner compartments 13 and the other the cells in side compartments 14, the cells in each group being simultaneously floodable. The cells 4 form a central floodable cell group 18, four corner cell groups 19 used for balancing the tank, and cell groups 20 used only for hydrocarbon storage. An empty tank 1 formed on land, or assembled whilst floating from a number of sub-elements, is controllably submerged by the flooding of compartments 13, 14 and 15, and is balanced whilst being submerged by the transfer of water between compartments 19. Once submerged with ribs 12 embedded in the seabed, all the cells are put into communication with one another, and totally flooded. The water in the cells is displaced to the necessary extent by the hydrocarbons whenever these are injected into the cells to be stored. Control of the flooding, loading and unloading operations may be effected from an emergent pillar located on the top of the tank (Fig. 3 not shown). The tank walls may be coated with anti-corrosive substances.